userfaultfd: non-cooperative: flush event_wqh at release time
authorMike Rapoport <rppt@linux.vnet.ibm.com>
Wed, 2 Aug 2017 20:32:24 +0000 (13:32 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 3 Aug 2017 00:16:13 +0000 (17:16 -0700)
commit5a18b64e3f02125be1c0ef777501ae38aafe2a24
tree88de1eff4972ac8c6acd682682e497f7a29f7eda
parentade9f91b32b964e83d294f4973d50083b08ef6fc
userfaultfd: non-cooperative: flush event_wqh at release time

There may still be threads waiting on event_wqh at the time the
userfault file descriptor is closed.  Flush the events wait-queue to
prevent waiting threads from hanging.

Link: http://lkml.kernel.org/r/1501398127-30419-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 9cd75c3cd4c3d ("userfaultfd: non-cooperative: add ability to report
non-PF events from uffd descriptor")
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/userfaultfd.c